Life history of the Atlantic sharpnose shark (Rhizoprionodon terraenovae) (Richardson, 1836) off the southeastern United States

The life history of the Atlantic sharpnose shark (Rhizoprionodon terraenovae) was described from 1093 specimens collected from Virginia to northern Florida between April 1997 and March 1999. Longitudinally sectioned vertebral centra were used to age each specimen, and the periodicity of circuli deposition was verified through marginal increment analysis and focus-to-increment frequency distributions. Rhizoprionodon terraenovae reached a maximum size of 828 mm precaudal length (PCL) and a maximum age of 11+ years. Mean back-calculated lengths-at-age ranged from 445 mm PCL at age one to 785 mm PCL at age ten for females, and 448 mm PCL at age one to 747 mm PCL at age nine for males. Observed lengthat-age data (estimated to 0.1 year) yielded the following von Bertalanffy parameters estimates: L∞= 749 mm PCL (SE=4.60), K = 0.49 (SE=0.020), and t0= –0.94 (SE=0.046) for females; and L∞= 745 mm PCL (SE = 5.93), K = 0.50 (SE=0.024), and t0= –0.91 (SE = 0.052) for males. Sexual maturity was reached at age three and 611 mm PCL for females, and age three and 615 mm PCL for males. Rhizoprionodon terraenovae reproduced annually and had a gestation period of approximately 11 months. Litter size ranged from one to eight (mean=3.85) embyros, and increased with female PCL.

Status survey of two Florida seaside sparrows and taxonomic review of the Seaside Sparrow assemblage

The original primary intent of this project was to determine the population status of two relatively obscure subspecies of Seaside Sparrows in Florida, the Smyrna Seaside Sparrow Cammodramus maritimus Eelonota) and the Wakulla Seaside Sparrow (Ammodramus maritimus juncicola) distinctiveness of these little known birds. As explained in the following section, a third and major objective appended to the project was to perform a taxonomic review of the entire Seaside Sparrow complex of nine subspecies. (170 page document)

Photographic analysis of natural and impounded salt marsh in the vicinity of Merritt Island, Florida

Qualitative analyses of available photographs and maps of Merritt Island, Florida provide a large-scale, historical perspective of ecological changes of the marshes in the vicinity. Sites that deserve closer scrutiny can be identified. Secondarily, such an analysis provides a geographical orientation essential for communication not only between newcomers and those familiar with the area, but also among those familiar with the area but who refer to sites by differing methods. Photographs and maps from various sources were examined. Below are listed what we consider to be the most useful subset of these for ecological and geographical assessment of salt marsh impoundments on Merritt Island, Florida. (Document has 25 pages.)

Flow and chemical characteristics of the St. Johns River at Jacksonville, Florida

This report will be of substantial value to water managers in developing the St. Johns River as a multiple resource. Evaluation of the capacity of the river to accept pollutants without adversely affecting other uses requires detailed data of flow and chemical characteristics and an understanding of how they interact. (66 page document)

Reconnaissance of the ground-water resources of Baker County, Florida

Ground-water is not widely used in Baker County, but the presence of a high equipotential area in the artesian system beneath the County made it necessary that the resource be understood insofar as this high affected the ground-water resources of Nassau and Duval counties which were being intensively studied and mapped. The method and rates of movement of ground-water from one point to another in the artesian aquifer are understood more fully by use of the data in this report. (PDF contains 30 pages)

Ground-water resources data of Charlotte, DeSoto, and Hardee Counties, Florida

Charlotte, De Soto, and Hardee counties are east-southeast of Tampa in west-central peninsular Florida, figure 1. In order to plan the future water-resource development of the area, information about the water resources is needed. To meet this need, the Water Resources Division of the U.S. Geological Survey, in cooperation with the Peace River Basin Board of the Southwest Florida Water Management District as part of the statewide cooperative program with the Division of Geology, Florida Board of Conservation, began a continuing hydrologic data collection program in July, 1963, as an initial step in the investigation and evaluation of the groundwater resources of Hardee and De Soto counties. A similar hydrologic data program commenced in Charlotte County in July, 1964. Previous work in Hardee and De Soto counties included a one year reconnaissance by the Division of Water Resources and Conservation, Florida Board of Conservation, which concluded in June, 1963, and resulted in a hydrologic report (Woodard, 1964). As an outgrowth of the hydrologic data program, a Map Series report portraying the chemical character of water in the Floridan aquifer in the southern Peace River basin was prepared in 1967 (Kaufman and Dion). The data contained herein constitute the basis for the Map Series report. Additional selected data, including records of wells and chemical analyses,, on the ground-water resources of the three county area are also included and are published to make the data available. (Document has 28 pages.)

Characterization of the sediments overlying the Floridan aquifer system in Alachua County, Florida

The primary purpose of this project is to attempt to improve the existing hydrogeologic information through lithologic and hydrogeologic characterizations of the sediments overlying the Floridan aquifer system in Alachua County. These sediments locally comprise both the intermediate aquifer system and associated confining beds and the surficial aquifer system. (PDF has 119 pages.)

The artesian water of the Ruskin area of Hillsborough County, Florida: interim report

The purpose of the investigation is to make a detailed study of the geology and ground water in the Ruskin area, especially as related to the problem of salt-water encroachment. The major objectives of the program includes: (1) An inventory of wells to determine their number and distribution, their depths and diameters, and other pertinent information. (2) A study of artesian pressures. (3) Analyses of water from selected wells to determine the location and extent of any areas in which the artesian water is salty. (4) A study of the surface and subsurface geology as related to the occurrence and movement of ground water. (5) An estimate of the quantity of ground water withdrawn. (PDF contains 24 pages.)

Interim report on the ground-water resources of Seminole County, Florida

Salt-water encroachment is undoubtedly the problem of most concern to users of ground water in Florida. This is a problem in many coastal areas where water levels are lowered excessively by heavy pumping. It is a problem also in some inland areas where the water-bearing formations contain salty water at relatively shallow depths. Among the coastal areas where wells have become contaminated with salt water are Pinellas County and the Miami area of Dade County. Inland areas where wells are likely to become contaminated with salt water include Seminole County and the southwestern part of Volusia County. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county with special emphasis on the problems associated with declining water levels and salt-water contamination. This report reviews briefly the progress of the investigation through February 1954. (PDF contains 43 pages.)

Interim report on the ground-water resources of Manatee County, Florida

A large part of western Manatee County is devoted to the growing of winter vegetables and citrus fruits. As in most of peninsular Florida, rainfall in the county during the growing season is not sufficient for crop production and large quantites of artesian water are used for irrigation. The large withdrawals of artesian water for irrigation result in a considerable decline of the artesian head in the western part of the county. This seasonal decline of the artesian head has become larger as the withdrawal of artesian water has increased. The lowering of the fresh-water head in some coastal areas in the State has resulted in an infiltration of sea water into the water-bearing formations. The presence of salty water in the artesian aquifer in parts of the coastal area of Manatee County indicates that sea water may also have entered the waterbearing formations in this area as a result of the decline of artesian pressure during the growing season. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county, primarily to determine whether salt-water encroachment has occurred or is likely to occur in the coastal area. (PDF contains 38 pages.)

Ground-water resources of the Stuart area, Martin County, Florida

Because the Stuart area is, at times, surrounded on three sides by saline water, the underlying fresh-water aquifer is vulnerable to salt-water encroachment. With progressively larger withdrawals of ground water for public and private supplies, the possibility of salt-water contamination of freshwater supplies is increased. (PDF contains 51 pages.)

Record of wells in the Ruskin area of Hillsborough County, FLorida

A detailed study of the geology and ground-water resources of the Ruskin area (fig. 1) was made during the period from 1950 to 1955, by the U. S. Geological Survey in cooperation with the Florida Geological Survey and the Board of County Commissioners of Hillsborough County. The results of this study are given in a report by Harry M. Peek entitled "The artesian water of the Ruskin area of Hillsborough County, Florida" and published by the Florida Geological Survey as Report of Investigations No. 21. This report contains tables of well records that were compiled from data collected during that investigation. The well-numbering system used in the tables is based on latitude and longitude. (PDF contains 88 pages.)

Interim report on the hydrologic features of the Green Swamp area in Central Florida

The Green Swamp area in central Florida is another area where man is developing agricultural land from marginal land. Though the area is by no means as extensive as that of the Everglades, the present efforts for its development are similar to the early efforts for developing the Everglades in that many miles of canals and ditches have been constructed to improve the drainage. Lest the early mistakes of the Everglades be repeated, the Florida Department of Water Resources considered that an appraisal of the physical and hydrologic features of the area was needed to determine the broad effects of draining and developing the swamp. This reconnaissance provides information required by the State of Florida for determining its responsibility and policy in regard to the Green Swamp area and for formulating future plans for water management of the area. Some of the features that have been determined are: the amount of rainfall on the area; the pattern of surfacewater drainage; the amount and direction of surface-water runoff; the direction of ground-water movement; the interrelationship of rainfall, surface water, and ground water; the effects of improved drainage facilities'; and the effects of the hydrologic environment on the chemical quality of water of the area.(PDF contains 106 pages.)

Reconnaissance of the ground-water resources of the Fernandina area, Nassau County, Florida

Practically all water for municipal and industrial use in the Fernandina area is supplied by artesian wells. In recent years, the use of artesian water in the area has increased to meet the needs of expanding industry and increasing population. The total industrial and municipal pumpage has increased from approximately 35 million gallons per day in 1941 to approximately 50 million gallons per day in 1959. Correlated with the increase in water use is the constant decline in the artesian pressure in the area. In many other areas in Florida, such a decline in artesian pressure has resulted in salt-water intrusion into the fresh-water supply.An intrusion of salt water in the Fernandina area would contaminate the existing fresh-water supply and would result in a hardship for the population and seriously injure the economy. Recognizing the threat to the fresh-water supplies of this area, the U. S. Geological Survey in cooperation with the Florida Geological Surveymade a reconnaissance to determineif there has been any intrusion of salt water into the fresh-water supply or if there is any danger of future intrusion. (PDF contains 28 pages.)

Evaluation of the quantity and quality of the water resources of Volusia County, Florida

This report amplifies and refines some of the data already issued covering the water resources of Volusia County, which were published as Report of Investigations No. 21. The work in the report was accomplished as a cooperative program between the Department of Natural Resources, the U. S. Geological Survey and the Board of County Commissioners of Volusia County. Volusia County is almost totally dependent upon the water which falls upon the county and has a recharge area contained along the western portion and the central portions of the county. Excellent water is produced in the areal recharge and it is anticipated that this data will expand the existing knowledge of the water resources to permit the development of a great capacity for existing utilities and to offset and solve some of the problems now in the area. (PDF has 71 pages.)